For crypto, we have upgraded to GMP 6.0.0, and added support for newer processors,
which will speed up crypto operations considerably.
Also, we are now using constant-time GMP functions to prevent side-channel attacks.
For caution, the GMP changes are enabled for new installs and Debian/Ubuntu builds only;
we will include them for in-net updates in the 0.9.27 release.

GMP 6.0.0 and jbigi/jcpuid native libraries, enabling significant speedups on newer architectures, and constant-time crypto operations (new installs and Debian/Ubuntu builds only, will include in the updates in the next release, 0.9.27)